After Sunday's performance, in which he allowed one hit over seven innings for his fifth win in six outings, the team isn't worried about the left-hander anymore.
"The whole thing when he was struggling was getting him back to how he can really throw," Houston manager Brad Mills said. "It sure looks like he's turning the corner and we've said that his last few starts. Today he kind of showed he's not at that corner now and he's moving on."
Michael Bourn drove in two runs with a double in Houston's three-run seventh to help the Astros avoid a three-game sweep against Cincinnati, which began the day with a half-game lead in the NL Central over St. Louis.
Reds rookie starter Mike Leake (7-2) was perfect in the fifth and sixth innings before Johnson's homer to left field with one out in the seventh made it 2-0. The home run extended his career-best hitting streak to nine games. Jason Castro followed with a single before a pinch-hit double by Jason Michaels chased Leake.
He was replaced by Arthur Rhodes, who gave up the two-run double to Bourn.
"The whole game was, I don't know ... those zeros up there on the scoreboard don't exactly tell the whole story," Leake said. "I wasn't locating very well today, and it just feels like I wasn't able to throw the ball where I wanted to."
The Reds tied a season low with three hits and were shut out for the major league-high 12th time this season. It also was the third consecutive Sunday in which they haven't scored.
"That is strange," manager Dusty Baker said. "When we hit, we are very good. But when we don't score, we don't score at all. Wandy has been really throwing the ball well. ... He was throwing his fastball up and out of the zone, away a lot. He bounces his breaking ball, and that is what he was doing today."
Rodriguez allowed a single to Joey Votto with two outs in the first inning before retiring the next nine batters. He walked Jonny Gomes with two outs in the fourth, but struck out Chris Heisey to end the inning.
"He had command of his fastball and he was able to keep them off his fastball by changing his breaking stuff," Mills said. "It really kept them off balance. When a guy is throwing strikes like that with everything, he's pretty special."
The left-hander walked Miguel Cairo to start the fifth, then reeled off nine straight outs again before being replaced by Lyon for the eighth inning.
"Cincinnati right now is hot hitting, so I tried to make good pitches today and that was the game," Rodriguez said.
The Astros had a chance to extend their lead in the fourth when Castro hit a ball to left field with Jeff Keppinger on second base, but Gomes made a diving catch to end the inning. Gomes barely snagged the ball before it hit the ground and quickly held it up to show he'd caught it before jogging off the field smiling broadly.
Pence's solo homer to the Crawford Boxes in left field in the second inning put Houston up 1-0.
Leake yielded seven hits and four runs while walking three in 6 1/3 innings.
Cincinnati 3B Scott Rolen, who has missed the last eight games with a strained right hamstring, thinks he could be ready to return Monday. Baker isn't so sure. "I've just learned over the years that if a guy tells me tomorrow, I think the day after tomorrow," Baker said. "If he's not 100 percent then ... I don't want to force it. When I get him back I want him back and not in and out, hopefully." ... The Astros got RHP Roy Oswalt a replacement of the trophy he won as MVP of the 2005 NLCS after the original award was destroyed when a tornado hit his parents' house in Mississippi in April. The award sat in a large box near his locker Sunday and he said he plans to send it to his parents. In what has become a daily occurrence, Oswalt talked about the possibility of being traded. When asked if he'd be disappointed if he isn't dealt by Saturday's non-waiver deadline, he responded: "I don't know what I'd feel. I've been pretty numb pretty much the last two weeks."